A Denver minted penny was pressed up against it probably using a vise.
The Circle you see is the rim of the penny. You can also make out the mintmark, the In God We Trust and of course the word Liberty.

@Larry Hobson
It is Definitely altered post Mint. It is not a Mint Error of any kind.

Suggestion.. We have a Error Coins forum here on CoinTalk. Any future threads you may have concerning possible Mint Errors you should create your threads there. Find out what yu have first then worry about value last.

Thanks guy's. I wasn't sure what it was, just knew it was odd looking. I wonder why someone would alter a coin like that? The back side looks normal just a little more worn.

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Some people are just crooks. They want to fool people into thinking that something is real but actually isn't. It could be done for money, or an attempt to fool someone. I do not recommend doing such practices.

Some people are just crooks. They want to fool people into thinking that something is real but actually isn't. It could be done for money, or an attempt to fool someone. I do not recommend doing such practices.

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Or maybe it was just some kid that used the vise on his Grandfathers work bench to squeeze coins together to see what would happen.

Or maybe it was just some kid that used the vise on his Grandfathers work bench to squeeze coins together to see what would happen.

(Not saying I know anything about juveniles experimenting as such)

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When I was a kid (before I started collecting), I would do crazy stuff like that all the time. I still have a dime that I whittled down and sanded until it was in about PO-02 condition. I don't know why I didn't see that as a possible option.